990 resultados para well failure


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This study was an examination of the strength of relations among covitality, and its underlying constructs of belief in self, emotional competence, belief in others, and engaged living, and two outcome variables; subjective well-being and depression. Participants included 361 Australian secondary school students (75 males and 286 females) who completed a series of online questionnaires related to positive psychological well-being in adolescents. The results from the first standard multiple regression analysis indicated that higher levels of belief in self, belief in others, and engaged living were significant predictors of increased subjective well-being. The results from the second standard multiple regression showed that higher levels of belief in self, belief in others, and engaged living were significant predictors of decreased feelings of depression. In both standard multiple regression models, the combined effect of the traits that comprise covitality was greater than the effect of each individual positive psychological trait.

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In this paper, we report on the growth and characterization of quantum dot−quantum well nanostructures with photoluminescence (PL) that is tunable over the visible range. The material exhibits a PL efficiency as high as 60% and is prepared by reacting ZnS nanocrystals in turn with precursors for CdSe and ZnS in an attempt to form a simple “ZnS/CdSe/ZnS quantum-well structure”. Through the use of synchrotron radiation-based photoelectron spectroscopy in conjunction with detailed overall compositional analysis and correlation with the size of the final composite nanostructure, the internal structure of the composite nanocrystals is shown to consist of a graded alloy core whose composition gradually changes from ZnS at the very center to CdSe at the onset of a CdSe layer. The outer shell is ZnS with a sharp interface, probably reflecting the relative thermodynamic stabilities of the parent binary phases. These contrasting aspects of the internal structure are discussed in terms of the various reactivities and are shown to be crucial for understanding the optical properties of such complex heterostructured nanomaterials.

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High mechanical stress in atherosclerotic plaques at vulnerable sites, called critical stress, contributes to plaque rupture. The site of minimum fibrous cap (FC) thickness (FCMIN) and plaque shoulder are well-documented vulnerable sites. The inherent weakness of the FC material at the thinnest point increases the stress, making it vulnerable, and it is the big curvature of the lumen contour over FC which may result in increased plaque stress. We aimed to assess critical stresses at FCMIN and the maximum lumen curvature over FC (LCMAX) and quantify the difference to see which vulnerable site had the highest critical stress and was, therefore, at highest risk of rupture. One hundred patients underwent high resolution carotid magnetic resonance (MR) imaging. We used 352 MR slices with delineated atherosclerotic components for the simulation study. Stresses at all the integral nodes along the lumen surface were calculated using the finite-element method. FCMIN and LCMAX were identified, and critical stresses at these sites were assessed and compared. Critical stress at FC MIN was significantly lower than that at LCMAX (median: 121.55 kPa; inter quartile range (IQR) = [60.70-180.32] kPa vs. 150.80 kPa; IQR = [91.39-235.75] kPa, p < 0.0001). If critical stress at FCMIN was only used, then the stress condition of 238 of 352 MR slices would be underestimated, while if the critical stress at LCMAX only was used, then 112 out of 352 would be underestimated. Stress analysis at FCMIN and LCMAX should be used for a refined mechanical risk assessment of atherosclerotic plaques, since material failure at either site may result in rupture.

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For clustered survival data, the traditional Gehan-type estimator is asymptotically equivalent to using only the between-cluster ranks, and the within-cluster ranks are ignored. The contribution of this paper is two fold: - (i) incorporating within-cluster ranks in censored data analysis, and; - (ii) applying the induced smoothing of Brown and Wang (2005, Biometrika) for computational convenience. Asymptotic properties of the resulting estimating functions are given. We also carry out numerical studies to assess the performance of the proposed approach and conclude that the proposed approach can lead to much improved estimators when strong clustering effects exist. A dataset from a litter-matched tumorigenesis experiment is used for illustration.

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Environmental data usually include measurements, such as water quality data, which fall below detection limits, because of limitations of the instruments or of certain analytical methods used. The fact that some responses are not detected needs to be properly taken into account in statistical analysis of such data. However, it is well-known that it is challenging to analyze a data set with detection limits, and we often have to rely on the traditional parametric methods or simple imputation methods. Distributional assumptions can lead to biased inference and justification of distributions is often not possible when the data are correlated and there is a large proportion of data below detection limits. The extent of bias is usually unknown. To draw valid conclusions and hence provide useful advice for environmental management authorities, it is essential to develop and apply an appropriate statistical methodology. This paper proposes rank-based procedures for analyzing non-normally distributed data collected at different sites over a period of time in the presence of multiple detection limits. To take account of temporal correlations within each site, we propose an optimal linear combination of estimating functions and apply the induced smoothing method to reduce the computational burden. Finally, we apply the proposed method to the water quality data collected at Susquehanna River Basin in United States of America, which dearly demonstrates the advantages of the rank regression models.

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Empty Heavens. Georges Bataille and the Question of Religion. The dissertation explores the question of religion in the texts of Georges Bataille (1897 1962), the controversial French avant-garde writer and philosopher. Passionate about religion throughout his life, Bataille devoted to it both critical analyses and personal meditations. In this study, Bataille s multifaceted relationship to religion is interpreted as expressing a passion for radical otherness. Bataille is approached as a characteristically modern thinker who, nevertheless, questions some landmarks of modernity insofar as modernity is interpreted as a triumph of secularization. The dissertation is situated at the intersection of comparative religion and philosophy of religion. Methodologically, the study resorts to theoretical contextualization and concept analysis. Acknowledging that Bataille s writings challenge the assumptions about coherent meaning taken for granted in traditional philosophical analysis, the study also pays attention to the literary means and, in general, the performative level of Bataille s texts. The study constructs three theoretical contexts for Bataille s question of religion first of all, the interpretation of Hegel in the mid-20th century French philosophy. In the first section of the study, Bataille s uneasy relationship with Hegel as mediated by Alexandre Kojève is explored. The motivation of his question of radical otherness is argued to arise from his struggle with the Hegelian Kojèvean notion of negativity. The second context is the dialogue with the Christian mystical tradition. Starting from the analysis of two Bataillean notions, dramatization and contestation , it is argued that, firstly, Bataille s approach to radical otherness is analogous to certain procedures of mystical texts while, secondly, the function of otherness providing no firm foundation in Bataille s texts differs from its function in mystical texts. In the third section of the study, Bataille s quest for otherness is concretized by analyzing his views on otherness of other person, on violence, and on death themes that are brought together in Bataille s lasting interest in sacrifice. Bataille s understanding of sacrifice is proportioned to social scientific and philosophical discussions on sacrifice. It is argued that the commitment to the idea of sacrifice accounts for a partial failure in the Bataillean approach to otherness, the otherness of other person remaining its (at least half) blind spot. The study presents an overview of Bataille s thought on religion. It brings out Bataille s view of the paradoxical fundamental yet impossible role of otherness in the construction of human world, as well as his understanding of religious representations as both covering over and indicating this otherness. It describes Bataille s atheological mysticism as a peculiar modern form of religiosity, as an ambivalent mourning for and exaltation of fundamental loss.

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The purpose of this research is to extend an understanding of how Black and White South African consumers' causal attributions for major household appliance performance failures impact on their anger and subsequent complaint behaviour. A survey was administered to Black and White South African consumers who were dissatisfied with the performance of a major household appliance item. Respondents resided in a major metropolitan area. The findings showed that, compared to Whites, the Black South Africans felt a low but significantly higher external locus of causality and lower control, and experienced a higher level of anger regarding product failure. The level of anger determined the decision to take complaint action, but racial group determined the type of action taken. Blacks complained more actively to retailers and engaged more in private complaint action than Whites. These findings may show that Black South Africans are developing a more individualistic orientation as consumers. Therefore, researchers should consider the effect of cultural swapping when researching consumer behaviour in multi-cultural countries. Implications for retailers in terms of complaint handling are indicated.

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Underground tunnels are vulnerable to terrorist attacks which can cause collapse of the tunnel structures or at least extensive damage, requiring lengthy repairs. This paper treats the blast impact on a reinforced concrete segmental tunnel buried in soil under a number of parametric conditions; soil properties, soil cover, distance of explosive from the tunnel centreline and explosive weight and analyses the possible failure patterns. A fully coupled Fluid Structure Interaction (FSI) technique incorporating the Arbitrary Lagrangian-Eulerian (ALE) method is used in this study. Results indicate that the tunnel in saturated soil is more vulnerable to severe damage than that buried in either partially saturated soil or dry soil. The tunnel is also more vulnerable to surface explosions which occur directly above the centre of the tunnel than those that occur at any equivalent distances in the ground away from the tunnel centre. The research findings provide useful information on modeling, analysis, overall tunnel response and failure patterns of segmented tunnels subjected to blast loads. This information will guide future development and application of research in this field.

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A 17-year-old white adolescent had a history of chronic diarrhea, delayed puberty, and growth failure. Investigations excluded cystic fibrosis, Shwachman syndrome, and endocrine causes of growth failure. Severe steatorrhea was diagnosed from fecal fat studies, and a jejunal suction biopsy showed total villus atrophy, consistent with a diagnosis of celiac diseases. Following introduction of a gluten-free diet, his appetite and growth improved, but he continued to have abdominal discomfort and loose offensive bowel motions. One year later, severe steatorrhea was present. A repeat jejunal biopsy showed partial recovery of villus architecture. Serum immunoreactive trypsinogen level was low, which was highly suggestive of exocrine pancreatic failure. Results of quantitative pancreatic stimulation test confirmed the presence of primary pancreatic insufficiency. After introduction of oral pancreatic enzyme supplements with meals, his gastrointestinal symptoms resolved and growth velocity accelerated. Previously, primary pancreatic insufficiency has only been described in elderly patients with long-standing untreated celiac disease. This case, however, emphasizes that pancreatic failure can occur with celiac disease at any age. Determination of a serum immunoreactive trypsinogen level should be considered a useful screening tool for pancreatic insufficiency in patients with celiac disease who have not responded to a gluten-free diet.

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Jakke Holvas: A Critique of the Metaphysics of Economy The research problem of this dissertation is the commonly held opinion according to which everything has become a question of economy in the present day. Economy legitimates and justifies. In this study, the pattern of thinking and conceptualizing in which economy figures as the ultimate reason is called the metaphysics of economy. The defining characteristic of the metaphysics of economy is its failure to recognize non-economic rules, ethics, or ways of existence. The sources included in the study cover certain classics of philosophy (Plato, Aristotle, Friedrich Nietzsche) and sociology (Karl Marx, Max Weber, Marcel Mauss), as well as the more recent French social theory (Jean Baudrillard, Michel Foucault). The research methods used are textual analysis and evaluation of concepts by means of historical comparison. The background to the study is given by the views of historians and sociologists according to whom traditional forms have ceased to exist and the market economy become established as the western system of values. The study identifies points of transition from the traditional forms to economic values. In addition, the dissertation focuses on the modern non-economic forms. The study examines the economic and ethical meanings of gift in antiquity in Homer, Plato, and Aristotle. Following Marcel Mauss, the study analyzes the forms and principles of gift exchange. The study also applies Nietzsche’s philosophy to evaluate under what conditions giving a gift becomes an act of exercising power that puts its receiver into debt. The conclusion of the study is that the classics of philosophy and sociology can rightly be interpreted in terms of the metaphysics of economy, but they also offer grounds for criticizing this metaphysics, even alternatives. One such alternative is non-economic archaic ethic. The study delineates a duality between economy and non-economy as well as creating concepts which could be used in the future to critically analyze economy from a position external to the economic system of concepts.

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It is now widely acknowledged that student mental well-being is a critical factor in the tertiary student learning experience and is important to student learning success. The issue of student mental well-being also has implications for effective student transition out of university and into the world of work. It is therefore vital that intentional strategies are adopted by universities both within the formal curriculum, and outside it, to promote student well-being and to work proactively and preventatively to avoid a decline in student psychological well-being. This paper describes how the Queensland University of Technology Law School is using animation to teach students about the importance for their learning success of the protection of their mental well-being. Mayer and Moreno (2002) define an animation as an external representation with three main characteristics: (1) it is a pictorial representation, (2) it depicts apparent movement, and (3) it consists of objects that are artificially created through drawing or some other modelling technique. Research into the effectiveness of animation as a tool for tertiary student learning engagement is relatively new and growing field of enquiry. Nash argues, for example, that animations provide a “rich, immersive environment [that] encourages action and interactivity, which overcome an often dehumanizing learning management system approach” (Nash, 2009, 25). Nicholas states that contemporary millennial students in universities today, have been immersed in animated multimedia since their birth and in fact need multimedia to learn and communicate effectively (2008). However, it has also been established, for example through the work of Lowe (2003, 2004, 2008) that animations can place additional perceptual, attentional, and cognitive demands on students that they are not always equipped to cope with. There are many different genres of animation. The dominant style of animation used in the university learning environment is expository animation. This approach is a useful tool for visualising dynamic processes and is used to support student understanding of subjects and themes that might otherwise be perceived as theoretically difficult and disengaging. It is also a form of animation that can be constructed to avoid any potential negative impact on cognitive load that the animated genre might have. However, the nature of expository animation has limitations for engaging students, and can present as clinical and static. For this reason, the project applied Kombartzky, Ploetzner, Schlag, and Metz’s (2010) cognitive strategy for effective student learning from expository animation, and developed a hybrid form of animation that takes advantage of the best elements of expository animation techniques along with more engaging short narrative techniques. First, the paper examines the existing literature on the use of animation in tertiary educational contexts. Second, the paper describes how animation was used at QUT Law School to teach students about the issue of mental well-being and its importance to their learning success. Finally, the paper analyses the potential of the use of animation, and of the cognitive strategy and animation approach trialled in the project, as a teaching tool for the promotion of student learning about the importance of mental well-being.

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Children with end-stage liver disease now form a major sub-group of patients considered suitable for liver transplantation (ltp), and enjoy better survival statistics after transplantation than do adults. Since June 1984, a paediatric ltp programme has been developed in Brisbane with an initial working relationship and ongoing close links with two USA centres (Pittsburgh, and the UCLA Medical Center). Fourteen children with end-stage liver disease have been referred to the Queensland Liver Transplantation Programme for formal assessment. Following frank, informed discussion with their parents, 10 of these children were offered the option of ltp. During the transition stage, two infants with biliary atresia were referred to UCLA at their parents' request and, subsequently, eight children aged from 9 months to 6 years have been placed on a transplant candidacy list in Brisbane. A donor procurement team with access to a Queensland Government jet has been available to cover all mainland States except Western Australia. Six of the children have now had orthotopic ltp (two children at the UCLA Medical Center; four children at the Royal Children's Hospital, Brisbane). One UCLA patient died with a non-functioning graft, and one Brisbane patient died 5 weeks post-transplant with rejection, hepatic artery thrombosis and sepsis. The other four children are alive and well, three with normal liver function and one with unexplained intrahepatic cholestasis, during the 1-20 month follow-up to date. Three further children have died of their liver disease without a donor of an appropriate blood group and size being found, and one patient still awaits a suitable donor. The experience of these authors suggests that ltp is a major advance in the treatment of paediatric liver disease, and that the procedure can be carried out successfully in Australia with initial results comparable with leading overseas centres. The procedure requires the full array of services of a major paediatric tertiary care facility, an intensive team effort with awareness of the special needs of children, and a widespread procurement capability. A major problem for Australia is the procurement of sufficient numbers of optimal paediatric donor livers.

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A prospective, population-based study was conducted to assess the impact of twin pregnancy on a woman's physical and emotional well-being. It compared women's reports of their general health, experience of a range of specific symptoms, and emotional well-being during pregnancy using the Edinburgh Postnatal Depression Scale. The subjects were 147 women expecting twins and 11,061 women expecting a single child who completed questionnaires at both 20 and 32 weeks’gestation as part of the Avon Longitudinal Study of Pregnancy and Childhood. Results suggested that women expecting twins experienced poorer physical well-being but not poorer emotional well-being than those expecting a single child, even though a significant association between poor health and emotional well-being was found for the population as a whole. It was suggested that the transitory nature of a twin pregnancy, the “special’ status of a twin pregnancy, greater social support, and modified expectations about health may buffer the effects of poor physical health on emotional well-being in a twin pregnancy. The findings should alert those who care for women expecting twins to the greater physical stress these women may feel.

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The effects of life events, social support and the emotional well-being of partner on the emotional well-being of the mother during pregnancy was examined within the cultural contexts of Britain and Greece. It was proposed that social support, impact of life events and relationship of the mother with her partner would be affected by the different social structures of each culture and would influence emotional well-being. A sample of 200 Greek and 156 British mothers and their partners completed questionnaires which included a life event inventory, measure of social support and measure of emotional well-being (Crown-Crisp Experiential Index). Greek mothers were found to score significantly higher on measures of depression, anxiety and somaticism, experience more stressful life events (most relating to family issues) and report feeling less supported than British mothers. Life events, particularly those relating to family stresses were found to predict poor emotional well-being among Greek mothers. For British mothers, social support was the strongest predictor of emotional well-being. Findings were discussed in the light of differences in social structure and it was suggested that future research might focus on the disruption of established social support structures rather than the differences in availability of social support per se when considering maternal emotional well-being.

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The effect of psychosocial factors on the emotional well-being of mothers following childbirth were examined within the cultural contexts of Britain and Greece. These mothers had already completed questionnaires during pregnancy and were contacted a second time in the postpartum period. At 4–6 weeks postpartum a sample of 165 Greek mothers and 101 British mothers and their partners completed the Edinburgh Postnatal Depression Scale. The relationship between mothers' EPDS scores and measures of emotional well-being in pregnancy (CCEI), social support, life events, fathers' EPDS score, and father's perception of change in partner was examined in each culture. No difference in the distribution of EPDS scores in each culture was found. Social support and life events were found to predict postnatal depression in both cultures. Additionally, in Greece, emotional well-being in pregnancy made a separate contribution to prediction. The major difference between the two cultures was in the relationship between mothers and their partners. Greek fathers were more emotionally and physically distanced from their partners during pregnancy, birth and early parenthood and perceived their partners as being more changed by the transition to parenthood. These differences were not reflected in differences in emotional well-being possibly because they accord with social expectation in each culture.